Wednesday, November 27, 2013

Ask Well: Genetic Testing for Breast Cancer

Tali Shalev, 40, getting a CT scan at a hospital near Tel Aviv last month. Ms. Shalev, whose mother developed breast cancer at 50, tested positive for a genetic mutation. During a prophylactic double mastectomy, a cancerous lesion was found, and Ms. Shalev learned that the disease had spread to her bones.Rina Castelnuovo for The New York TimesTali Shalev, 40, getting a CT scan at a hospital near Tel Aviv last month. Ms. Shalev, whose mother developed breast cancer at 50, tested positive for a genetic mutation. During a prophylactic double mastectomy, a cancerous lesion was found, and Ms. Shalev learned that the disease had spread to her bones.
Some Israeli doctors want Israel to conduct a national screening campaign to test all Jewish Israeli women of Ashkenazi descent for harmful genetic mutations that heighten the risk of breast and ovarian cancer. The debate is detailed in the article, “In Israel, a Push to Screen for Cancer Gene Leaves Many Conflicted.”
Most American Jews are Ashkenazi, meaning their families originated in Eastern and Central Europe and they may be wondering if they should seek genetic testing.
Here are answers to some questions about genetic testing for the three common harmful mutations in the BRCA1 and BRCA2 genes.
Q.
I’m an Ashkenazi Jewish woman. Should I be tested for the mutations in the BRCA1 and BRCA2 genes?
A.
If you have been diagnosed with breast or ovarian cancer or have a family history of breast or ovarian cancer, you may want to be tested for one of the mutations in the BRCA1 and BRCA2 genes that are common among Ashkenazi Jews. Knowing your carrier status may help you evaluate your future risk and can be useful information for other family members. If you have cancer, the information can help shape treatment and alert you to other risks (such as a heightened risk for ovarian cancer if you have breast cancer).
While some Israeli doctors want to expand testing and make it routine, general practice in the United States has not encouraged genetic testing for individuals who are cancer-free and don’t have a family history.
But for Ashkenazi Jews, the bar for genetic testing is not as high as for the general population, said Dr. Susan M. Domchek, executive director of the Basser Research Center for BRCA at the University of Pennsylvania’s Abramson Cancer Center.
“If you’re Jewish, we have a low threshold for testing,” Dr. Domchek said. “If you have an aunt who had breast cancer at 51 and you want testing, that’s O.K.”
Keep in mind that the odds of testing positive are fairly low — only one in 40 Ashkenazi Jews, or 2.5 percent, carry the mutation. That is higher than the rate in the general population, in which fewer than 1 percent carry these mutations, but it means you have a 97.5 percent chance of testing negative.
Remember that a family history includes relatives on both sides of the family, including your father’s side.
“People ignore the father’s side of the family, and they shouldn’t,” said Dr. Domchek. “Women will come to us and say there’s no family history, but actually the dad was Ashkenazi Jewish and the dad’s mother had breast cancer at 40 – that’s a significant family history.”
Q.
What if I don’t know much about my family history?
A.
Many Ashkenazi Jews have limited information about their family because they lost relatives in the Holocaust. Others come from small families that don’t provide a lot of clues, and families everywhere become estranged and keep secrets. One reason Israeli doctors want to do broad-based screening of Ashkenazi Jewish women is so that individuals are not dependent on family members for information.

Nevertheless, Dr. Domchek emphasized that there is still some uncertainty about what it means if a woman tests positive for a mutation and no one in her family has had cancer. Research is trying to resolve questions about what the risk is in these cases. “It’s a challenge to give an individualized risk assessment,” she said.
If you are concerned because you have limited information about your family, genetic counseling may help clarify whether you should pursue testing.
Q.
What does the test consist of? How much does it cost? Will insurance cover it?
A.
The genetic test is a blood test, often accompanied by genetic counseling. Testing for the three specific BRCA1 and BRCA2 mutations common among Ashkenazi Jews generally costs between $300 and $500 for all three. Insurance coverage varies and may be more likely to pick up the cost if the individual has a clear family history of breast or ovarian cancer. Genetic testing of men is generally not covered, Dr. Domchek said.
Q.
What does a positive result mean?
A.
A woman who tests positive for a mutation will be given a range of risk for developing breast cancer and ovarian cancer during her lifetime that takes her family history into account, but assessing individual risk is a challenge, Dr. Domchek said. “If the only history is a mother who developed breast cancer at 55 and the mother has four sisters and no one else has cancer of any sort,” then the woman’s risk will be deemed lower than if several of her aunts have cancer, she explained.
While about 12 percent of women in the general population will develop breast cancer at some point in their lives, 55 percent to 65 percent of women with a harmful BRCA1 mutation and around 45 percent of those with a harmful BRCA2 mutation will develop breast cancer by age 70,according to the National Cancer Institute. While about 1.4 percent of women in the general population will develop ovarian cancer, some 39 percent of carriers of a harmful BRCA1 mutation and 11 percent to 17 percent of carriers of a harmful BRCA2 mutation will develop ovarian cancer by age 70.
Q.
What factors should I weigh when considering prophylactic surgery?
A.

Choosing prophylactic surgery is a difficult and highly personal decision. Many doctors emphasize the importance of removing the ovaries, because the mutations increase the risk of ovarian cancer, which is harder than breast cancer to detect at an early stage. Israeli physicians urge women to undergo ovary removal as soon as they have had their children, preferably by the age of 40. Removing the ovaries also reduces the risk of breast cancer considerably.

The choice of whether to have a prophylactic double mastectomy is complex. Close monitoring and surveillance of the breasts with frequent magnetic resonance imaging scans and clinical breast exams is another option, doctors say. Over time, however, doctors say many women tire of the constant checkups, especially if they are called back for frequent biopsies and some eventually opt for mastectomies as a result.

Both oophorectomy and mastectomy are difficult operations that have serious side effects. Breast reconstruction often leads to infections and other complications and many women are disappointed by the look and feel of their new breasts. Removing the ovaries robs women of important hormones and plunges them into menopause overnight, leading to hot flashes, reduced sex drive and heightened risks of heart disease and bone loss. Hormone replacement treatment or other medication is often required.